body {
  background: #000;
}
#main {
  background-color: black;
}
canvas {
  display: block;
}
.waves {
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  /* 禁用 canvas 上的鼠标和触摸事件 */
  pointer-events: none;
}
